Method and device for injection moulding and assembling plastic parts

ABSTRACT

The invention concerns a device for injection molding comprising a first fixed half-mold and a second half-mold mobile in direction (y) of the side blocks of an injection molding machine. Between the first and the second half-molds are mounted first and second intermediate elements mobile in the direction of the side blocks. The first and the second intermediate elements comprise each a mold support pivoting relative to a base about s pivoting axis. Centering elements are used to center the intermediate elements relative to the half-molds upon the opening and closure of the injection molding device.

The invention relates to a device for manufacturing plastic parts, inparticular plastic parts consisting of several individual parts,according to the preamble of the independent patent claims.

Devices are known form the state of the art, which are suitable formanufacturing parts which consist of one or more plastic components.

The European patent EP 1155802 of the same applicant shows an injectionmoulding device with two production planes (parting planes) with arotary system which is arranged between a stationary and a moving mouldpart, and serves for holding a middle mould part. The middle mould partis held by a lower and an upper crossmember by way of holding means andis movably arranged about a vertical axis. The crossmembers are guidedon the tie-bars of an injection moulding machine. In order to compensatethe weight of the middle mould par; the lower crossmember, whenrequired, is supported on the machine bed of the injection mouldingmachine. The holding means are arranged displaceable relative to oneanother, so that the middle mould part may be exchanged. In a firstproduction plane, a first material component is injected into a cavityso that a first part arises. The part of the fist material componentremains sticking to the middle mould part on opening the mould, and isbrought with this into the second production plane by rotating themiddle mould part, where, after the closure of the mould, it is activelyconnected to a second material components. The middle mould part issupported on the tie-bars of an injection moulding machine by way ofholding devices.

EP0895848 from Ferromatik Milacron Maschinenbau GmbH shows a furtherdevice with two parting planes. A middle mould part is arranged betweena stationary and a movably arranged mould part, and this middle mouldpart is mounted in a lower and an upper crossmember, and is supported ona machine bed of an injection moulding device. The middle part isrotatably arranged about a vertical axis by 118° and comprises cavitiesonly on two sides. The bearing in the region of the upper crossmembermay be opened, so that the middle part may be removed.

EP 1110449 (hereinafter EP'449) of Krauss Maffei Kunstofftechnik GmbHshows an injection moulding device with two production planes, with astationary and a movable mould half. A mould middle part is arrangedbetween the two mould halves, and is held on one side by way of a guideadmitted in the machine bed of an injection moulding machine, and isrotatably arranged about an axis. The injection moulding machine isadapted to meet these special demands. The device described in EP'449 issuitable for manufacturing parts of several plastic components.

In PCT/DK01/0699 (her inter PCT699), of Jes Gram, the basic concept fora method with which an assembly of two identical parts is effected bywelding these to one another in at least one parting plane is described.The device suggested for implementing the method comprises two middleparts which in each case are rotatably arranged about an axis, and whichmay be opened and closed with the injection mould. PCT699 generallydescribes a device for manufacturing a single hollow body, in that afirst half-shell is manufactured in a first injection moulding plane,and a second hail-shell in a second injection moulding plane, and thenby way of rotating the middle parts about their axes by 180° andsubsequent closure of the injection mould with a uniformly opened mould,i.e. both parting planes are opened symmetrically, are connected to oneanother with a material fit. The material-fit connection between the twohalf-shells is effected by way of joining the melted base material as aresult of the closure movement of the mould. A heat source is appliedfor the melting, which is placed laterally next to the device. A singlehollow body arises per cycle. In particular, one may not deduce fromPCT'699 how the middle parts have to be mounted in the injection mould,so that a perfect functioning may be ensured. The device suggested inPCT699 for implementing the method provides no answers to questionswhich are essential for carrying out the method. The man skilled in theart has no hint from PCT699, amongst other things also on account of thevery schematic, imprecise description, as to how a device forsuccessfully implementing the method should look in detail.

U.S. Pat. No. 4,744,741 (hereinafter US'741), John B. Glover et al.,shows a device with a stationary first mould half and a second mouldhalf which is movably arranged with respect to this. A first and asecond, middle part in each case rotatable about an axis are arrangedbetween these two mould halves, and these middle parts cooperate in themiddle with a direct positive fit and form the inner part of a cavity. Afurther mould part consisting of two mould halves in the closedcondition is arranged about the rotatable middle parts and temporarilyforms an outer annular part of an injection mould. In the middle, thetwo rotatable middle parts cooperate directly along a middle partingplane. Two first parts are manufactured simultaneously in a first andthird parting plane. The device is subsequently opened in a uniformmanner and the two first part, by way of the rotatable middle parts, arejoined together with a second part which is held by the middle, annularmould part. According to the description, the two first parts are stillin the part-plastic condition when they are connected to the first part,so that the first and the second part stick to one another. An externalheating is provided in the case that the material is no longersufficiently fluid, in order to melt the material again. The devicedescribed in US'741 serves for manufacturing tube unions or tubeconnection pieces which are to be pushed over the ends of tubes to beconnected, and comprise seals which are manufactured in the same deviceand are connected to the outer part in the above described way andmanner by way of the rotatable middle parts. The exact construction ofthe injection mould described in US'741 as well as their coordinationmay not be deduced from the document. Amongst other thing, one may notdeduce from the description as to what the demands on an injectionmoulding machine are.

A significant disadvantage of the devices known from the state of theart lies in the fact that parts are joined together via the main toolmovement by way of the closing of the mould. This leads to a lowprecision and a slowing of the process, since the closure mechanism ofthe injection moulding machine which is responsible for the closuremovement is not suitable for assembly. Furthermore, with a device with amultitude of cavities per closure plane, it is not possible to assemblein an individual manner.

It is the object of the invention to specify a method and a device forthe manufacture of complex parts, in particular assembly injectionmoulding products of several parts, which avoid the disadvantages of thestate of the art.

One aim of the invention is based on the implementation of an injectionmoulding method with which two or more equal or different parts of thesame or different material components are actively connected to oneanother in a direct manner or indirect manner. With a preferredembodiment, the individual parts preferably in the region of a first anda second parting plane of an injection moulding device according to theinvention are manufactured with several mould halves, and are activelyconnected to one another in the region of the third parting plane of thesame injection moulding device, preferably whilst utilising the closureforce, or closure movement of the injection moulding device. Whenrequired, it is envisaged as a rule for further parts to be injectionmoulded in the first and in the second parting plane during the activeconnection in the region of the third parting plane.

Alternatively or to supplement this, the active connection of at leasttwo parts by way of a separate active connection means which preferablyin the region of cavities is integrated into at least one of the mouldhalves or mould carriers, and as a rule steps into action with a closedinjection moulding device, i.e. when the parting planes of the injectionmoulding device are closed or with a closing injection moulding device.In a preferred embodiment, a slide is arranged in the region of thecavities, which is designed such that generally with a closed injectionmoulding device, it may bring a first part into active connection with asecond one by way of a relative movement. One advantage of this activeconnection means lies in the fact that the injection moulding device maybe closed independently of the active connection of the at least twoparts, and the active connection is decoupled from the closure movementof the injection moulding device. A possibility of improving theadaptation or of adjustment bath and/or speed and/or force) of theprocedure arises due to this, without disadvantageously affecting themachine cycle. Depending on the field of application, it would otherwisebe necessary to reduce the operating speed since otherwise an optimaljoining-together of the parts to be actively connected would not beensured, or the parts would get damaged. Accordingly only a reducedproduction speed would be possible without the active connectionmechanism according to the invention. The active connection mechanism ispreferably operated in a hydraulic or electrical manner and whenrequired comprises sensors which monitor the procedure. The activeconnection mechanism when required is designed such that an assembly ispossible which takes account of the cavities, i.e. is matched to each ora group of cavities.

The device for carrying out the method according to the invention ispreferably designed such that it may be applied together withcommercially available, standardised injection moulding machines. Theinjection moulding device is therefore designed such that it finds spacebetween tie-bars of an injection moulding machine. The moving parts ofthe injection moulding device are preferably mounted or supportedopposite the tie-bars of the injection moulding machine, or the machinebed. The movement of the moving parts of the injection moulding deviceis at least matched to the movement of the injection moulding device byway of at least one coordination mechanism. Preferred is a coordinationmechanism which matches the travelled paths of the moved parts to oneanother, depending on the parting plane, such that the middle parts arerotated efficiently and when required simultaneously.

With a further preferred embodiment of a device according to theinvention, the individual parts are preferably manufactured and/orconnected to one another in the region of four parting planes. It isenvisaged for further parts to be injection moulded as a rule during theactive connection. An active connection mechanism guarantees theefficient assembly.

A preferred form of the active connection is effected by peripherallyinjecting the first and the second part. For this purpose, plasticmolten is introduced into cavities in the region of the third partingplane by way of a plastification unit which as a rule is arrangedlaterally or above the injection moulding device, so the at least onefirst and the at least one second part are actively connected. Theadditional cavities which are required for the peripheral injection, inthe region of the third, middle parting plane, are for example formed byway of retracting a core, or by way of specially configured concavemould halves which cooperate with corresponding, convexly configuredcounter-sides in the region of the first and second parting plane.

A device suitable for carrying out the method comprises a first,stationarily arranged mould half and a second mould half which ismovably arranged with respect to the first one along guide means(tie-bars, guide rails). At least two middle parts which are eachrotatable about a rotation axis are arranged between the first and thesecond mould half. The rotation axes of the two preferably prismaticallydesigned middle parts as a rule are aligned parallel or at a 90° angleto one another. The middle parts are guided along guide means. Thetie-bars of the injection moulding machine or other guide means, whiche.g. are actively connected to a machine bed of an injection mouldingmachine, serve for the linear guiding of the middle parts, depending onthe field of application. With a further embodiment, cantilever-likeelements are attached in the region of the outer two mould halves and/orthe machine plates, and serve for holding and mounting the middle parts.The middle parts are arranged rotatable about an axis standingperpendicular to the main movement direction of the injection mouldingmachine, and in a displaceable manner parallel thereto, so that they maybe rotated about their axis given an opened injection moulding device.The middle parts may be arranged in a suspended or horizontallyprojecting manner, according to the field of application. As a rule, themiddle parts comprise all even number of corresponding side surfaceswhich are arranged parallel to one another in pairs.

In the region of the third parting plane, the parts from the first andthe parts from the second parting plane are preferably releasably orunreleasably actively connected to one another by way of a frictionconnection, snap-connection, press connection, by way of peripheralinjection with the same or with a further plastic component, ultrasonicwelding or frictional welding. The active connection is effected via anactive connection mechanism of the initially described type, dependingon the field of application.

With one device, one or more further mould parts may be provided betweentwo middle parts, and these mould parts in combination with the middleparts rotatable about an axis serve for forming one or more cavities.The mould part is designed of one piece or of several pieces, such thatthe actively connected parts may be removed. The mould halves and/or themiddle parts when required comprise a slide which ensures a betterremoval ability of the manufactured parts from the mould. The kinematicsof the parts moving towards one another are matched to the additionalelement, or take this into account.

The method described in PCT699 may not be realised with conventionalinjection moulds. For this reason injection moulds which take thespecial requirements into account are needed. In contrast to theconventional injection moulds, the injection moulding devices suitablefor carrying out the method comprises significantly more moving parts,which must be brought into a precise coordination with one another, sothat the opening and closure of the injection moulding device isguarantee without collision.

The injection moulding device according to the invention is suitable forthe manufacture and assembly of multi-part plastic parts. With this,plastic parts are manufactured by injection moulding in the region of atleast two parting planes, and assembled or actively connected in theregion of at least one further parting plane. Alternatively orsupplementarily, the parts are processed and/or assembled and/or removedoutside in the region of the free side surfaces of the middle parts.

The invention amongst others is suitable for the manufacture of closuresfor drinks packs. For example multi-part “push-pull” closures with abase and with a cap which is arranged displaceable with respect to thebase, may be manufactured and assembled in an injection moulding device.Thereby, the individual parts may in each case individually consist ofone or more material components. The assembly is effected either via theclosure movement of the injection moulding device or via a separateactive connection device which actively connects the parts after theinjection moulding device is closed. With regard to the separate activeconnection device, it is for example the case of at least onehydraulically actuated slide arranged in the region of the cavities, byway of which the parts execute a relative movement towards one anotherand are thus assembled.

The possibility exists for example of manufacturing medical syringes orsimilar parts, by way of manufacturing an outer part in a first partingplane, and a plunger with a seal consisting of one or more materialcomponents in the second parting plane. After opening the injectionmoulding device and the subsequent rotating of the first and the second,middle part, the plunger is inserted into the outer part on closure ofthe injection moulding device. One succeeds in preventing any germs fromoccurring due to the high temperature. Alternatively, there exists thepossibility of including a fourth parting plane in the production andcarrying out the assembly externally.

The middle parts of the injection moulding device are preferablyconfigured in a parallelepiped manner and comprise four side surfaces,of which in each case two are arranged parallel to one another. Themiddle parts as a rule are rotated by 90° or 180° with each operatingstep, so that parts manufactured in tie region of the first or thesecond parting plane, after one or two working steps, get from the firstor the second parting plane respectively into the region of the thirdparting plane, where they are brought into active connection with oneanother. When required, further processing steps, which e.g. are carriedout by handling robots are provided in the stations between the partingplanes, the so-called intermediate or free stations. If desired, thereexists the possibility of providing free cavities, or parts sticking tothe middle par; with labels which are connected to new or existing partswith the next injection procedure. The intermediate stations whenrequired are used for cooling manufactured parts. The middle parts arepreferably endlessly rotatable about an axis with respect to thestationary parts of the injection moulding device. The supply of themiddle parts rotatably arranged about an axis with media such as water,air, oil and/or electricity, as well as sensor signals and command(control) variables is preferably effected coaxially via a lower and/orupper holding device. The holding devices for this purpose are designedsuch that they permit a coaxial leading of medium.

Parts which are manufactured or assembled in the parting planes arepreferably moved by way of the middle parts between the individualstations. For this purpose, the middle parts comprise active or passiveholding means. The middle parts as a rule comprise separate feeds forenergy, information and operating material such as current, water,hydraulic oil and air. The energy and media are preferably led throughthe rotation shafts of the middle parts, so that these may be infinitelyrotated about their axes.

The device described in PCT 699 has the disadvantage that no centring ofthe mould halves and/or the middle parts to one another is provided onopening and on closing the injection mould. As has been shown, inpractise it is however impossible, in particular with larger injectionmoulds, to position the components of the injection mould which mostlyweigh tons, in such a precise, manner that they are always harmonised toone another on closure of the mould. The result of this is that thehigh-precision and sensitive cavities may be damaged, so that a perfectfunctioning of the injection mould may no longer be insured.

On opening and closing an injection moulding device according to theinvention, the centring and alignment of the mould halves and the middleparts to one another represents a difficulty which must be overcome atall events. Since with regard to the components of the injectionmoulding procedure, it is usually the case of metal blocks weighingtonnes which are opened and closed at a considerable speed, a centringof the mould may not be effected via the cavities alone. Centring meansare known from the state of the art, which are used for centringconventional injection moulds with only one parting plane. Thereby, itis generally the case of case of lugs which are attached in a projectingmanner at one side either on the stationary or the travelling mouldhalf, and engage into openings in the other mould half which areenvisaged for this. Since conventional injection moulds with only oneparting plane as a rule are only moved in one direction, the arrangementof the centring means as a rule does not represent any problem. However,with injection moulding devices with two rotatable middle parts, anexact positioning of the mould halves is only possible if the centringmeans have a special arrangement and design, which ensures an exactpre-centring and centring of the movable mould parts. If required, onedevice according to the invention has a two-stage centring with a priorpre-centring and a subsequent or superimposed fine centring. The mouldparts are captured by way of the pre-centring and subsequently broughtinto a precise alignment against one another by way of the finecentring.

In contrast to conventional injection moulds, the arrangement of thecentring means needs to meet special demands, so that the injectionmoulding device may be closed at all. The arrangements of centring meansknown from the state of the art are not suitable for this, since aclosure of the mould would not be possible. The centring means need tobe arranged such that the mould halves and the two middle parts may beclosed in the different positions which are envisaged for this. With theuse of centring lugs, this means that e.g. the first, stationary mouldhalf comprises four projecting centring lugs in the region of the fourcorners, which correspond with four centring sockets which are attachedon the corresponding side surfaces of the first mould middle part. Thesecond mould middle part on the corresponding side surfaces in turncomprises four projecting centring lugs which may be actively connectedto corresponding centring sockets of the first middle part and of thesecond movably arranged mould half on closure of the injection mouldingdevice. The centring lugs and centring sockets are designed such thatthey effect a capture and pre-centring of the moving parts, so thatthese in the case of a certain faulty position on closure, come to liein the correct end position, without the sensitive cavities becomingdamaged. The centring lugs and the centring sockets when required have acertain conicity at least in regions, which encourages the mutualalignment. For this reason, the centring means are preferably designedsuch that they ensure a centring of the mould before this is completelyclosed, or the sensitive regions of the cavities are actively connectedto one another. Alternatively or supplementarily, the middle partscomprise further centring means which are suitable for locking therotational movement of the middle parts about their rotation axis inpositions envisaged for this. With regard to the further centring means,it is usually the case of locking pins which engage into lockingopenings which are envisaged for this, and thus prevent a furtherrotation of the middle parts after reaching a defined end position. Thelocking pins are preferably hydraulically or electrically operated andcomprise a locking mechanism. With a parallelepiped middle part, thelocking openings into which the locking pin or pins provided for thisengage, as a rule are arranged at a 90° or 180°-angle, so that themiddle part may be fixed at a 90°- or 180° angle. The further centringmeans serve for fixing the middle parts on reaching an end position, sothat main centring means, e.g. in the form of centring lugs, may performthe fine centring.

The mountings of the middle parts and, if provided, of the further mouldhalves must meet particular demands, so that the injection mouldingdevice as a rule may be simply inserted and removed between the tie-barsof an injection moulding machine. The mounting further has the advantagethat it is suitable for application with conventional injection mouldingmachines and injection moulding devices with one or two middle parts.

A preferred embodiment of a mounting comprises a lower support whichdirectly or indirectly actively connected to the machine bed of theinjection moulding machine, is supported on this and or is guided alongthis. An upper support is effected by way of a crossmember which isactively connected to one or two tie-bars of the injection mouldingmachine and is guided along this. The crossmember and/or the lowersupport if required comprises a locking means which serves for lockingthe rotatable mould carrier in positions envisaged for this. Themounting is designed such that the middle parts are displaceable in thedirection of the tie-bars of the injection moulding machine. In thelower region, the support is for example effected by way of rails whichare supported on the machine bed of the injection moulding machine. Inthe upper region, the crossmember is actively connected to the tie-barsvia linear bearings. The linear bearings as a rule are designed suchthat they may be released from the tie-bars in a simple manner, forexample preferably in that the bearing shells are capable of beingparted in the vertical direction. One of the advantages lies in the factthat the mounting in the lower region has a slim design which permits asimple and time-saving removal between the tie-bars. By way of theguiding on both sides, it is ensured that the elements of the injectionmoulding machine are guided with a high precision. Furthermore, thereexists the possibility of providing the middle parts at the bottom aswell as at the top, with a drive or with a coordination mechanism.

The coordination of the components of an injection moulding deviceaccording to the invention with a stationary first and a moving secondmould half between which a first and a second, middle part rotatableabout their axes are consecutively arranged, is preferably effected byway of a coordination mechanism. One preferred embodiment of acoordination mechanism comprises three threaded spindles which arearranged essentially parallel to one another and which actively connectthe components of the injection moulding device to one another. Thecoordination mechanism comprises a first spindle which actively connectsthe first, stationary mould half to the second, travelling mould half.The spindle is divided into two and comprises a first half with apositive pitch and a second half with a negative pitch running counterto the first one. The spindle is actively connected to the mould halvesvia stationary spindle nuts, or axial bearings, attached on the mouldhalves. If then, the injection moulding machine is opened or closed, thefirst spindle rotates about its longitudinal axis. As a result of theoppositely directed spindle pitch of the first and second part of thespindle, the spindle middle of the first spindle is always located inthe middle between the first stationary and the second travelling mouldhalf. Alternatively, the possibility exists of fixedly arranging thespindle via a suitable support, and instead to rotatably arrange thespindle nuts. A spindle block on which a second and a third spindledivided into two are supported, is located in the region of the middleof the first spindle, wherein the second spindle actively connects thespindle block to the stationary mould half, and the third spindleactively connects the spindle block to the moving mould half. The secondand the third spindle are arranged such that the middle of the secondspindle is moved with half the speed of the first spindle, and themiddle of the third spindle is moved with 1.5 times the speed of themiddle of the first spindle. With reference to the speed of the movingsecond mould half, the middle of the second spindle moves with a quarterof the speed of the moving mould half, and the middle of the thirdspindle with three quarters the speed of the moving mould half. Themiddles of the third and second spindle are actively connected to thefirst and second, middle part of the injection mould and coordinate itsmovement with regard to the stationary and the moving mould half. Theeffect of the described coordination mechanism is that when opening theinjection moulding device, the distance between the two middle parts isalways double as large as the distance between the stationary mould halfand the first or the second, middle part and the travelling mould half.With this, one takes into account the fact that more space is demandedbetween the middle parts on rotating the middle parts about their axesthan in the first and the last parting plane.

The linear drive or the coordination of the moving parts in they-direction is effected by way of an active or passive spindle drive onone or two sides, by way of a coordinated rack drive, or actively, byway of a coordinated hydraulic drive, i.e. via hydraulic cylinder. Whenrequired or alternatively, a rack may be integrated into the railsystem. An active drive system is to be understood as a drive which hasits own energy supply and permits an automatic movement of the movingparts. A passive drive system is to be understood as a drive which isdirectly or indirectly connected to the main drive of the injectionmoulding machine. A preferred embodiment of a passive drive comprisescoordinated spindles.

A further embodiment of a coordination mechanism comprises six rackswhich are coordinated in pairs in three groups. In each case, two racksare directly or indirectly connected to one another via a pinion whichfor example is rotatably supported on one of the crossmembers. The rackswhich are allocated to one another in pairs and are arranged essentiallyparallel to one another carry out a relative movement to one another onopening and closure, and are actively connected to one another via atleast one toothed wheel which engages into at least one of the tworacks. One preferred embodiment is designed such that the pivot of thecoordinating toothed wheel moves roughly with half the relative speed.The division ratios of the speed and thus the travelled path is utilisedfor the positioning of the inner components such as e.g. the middleparts, which are arranged between the outer components. Other divisionrations may be achieved by way of several toothed wheels with adifferent diameter, which are actively connected to one another e.g. viaa pivot. The advantages of the spindle drive lie in the simpleconstruction and in the use of standardised components.

A further embodiment of a coordination mechanism comprises hydrauliccylinders which are actively connected to one another. By way of asuitable choice of the diameter of the cylinder or the exchanged oilvolume, one succeeds in moving the parts lying therebetween with thedesired speed. Hydraulic coordination mechanisms are either driven in anactive manner via a hydraulic pump or passively via driving hydrauliccylinders. An active monitoring of the position of the middle parts isprovided if required, in order to avoid incorrect positioning.

A method for manufacturing a multi-part product in an injection mouldingdevice according to the invention disclosed here, is describedhereinafter in a simplified manner.

In a first method step, at least one first and a second part aremanufactured essentially simultaneously in the first and the third outerparting plane with a closed injection moulding device by way ofinjecting liquid plastic into cavities allocated to one another. Duringthis, at least one first and a second part are actively connected by wayof at least one active connection means essentially simultaneously inthe region of the second parting plane. The injection moulding device issubsequently opened along the parting planes, and the two mould carriersare in each case rotated about their rotation axis about an angle of 90°or 180°. Thereby, the parts which have just been manufactured in thefirst and third parting plane remain sticking to the mould carriers andare co-moved with these. The parts which are actively connected in themiddle parting plane are moved by way of one of the mould carriers aboutan angle of 90°, and in this position are removed or ejected by way ofseparate ejectors, and collected below the injection moulding device.The injection moulding device is subsequently closed afresh and theprocess begins once again. In a preferred variant, on opening, thesecond, middle parting plane is opened roughly double as far as thefirst and third parting plane. This permits a more efficient, timesavingrotation. The active connection of the two first parts in the second,middle parting plane is preferably effected independently of themovement of the injection moulding machine. The active connection of thetwo first parts in the second, middle paring plane is effected in groupsof cavities allocated to one another independently of one another,depending on the field of application.

Preferably, one electric or hydraulic motor which is directly orindirectly actively connected to the middle parts is used per middlepart as a drive for the rotation of the generally parallelepiped upperparts of the middle parts about their rotation axes.

Embodiments of the invention are hereinafter explained in more detail byway of the subsequent figures. Shown schematically and greatlysimplified are in:

FIG. 1 a first embodiment of an injection moulding device with aninjection moulding machine;

FIG. 2 a second embodiment of an injection moulding device;

FIG. 3 a third embodiment of an injection moulding device, obliquelyform above;

FIG. 4 a fourth embodiment of an injection moulding device, obliquelyfrom above;

FIG. 5 a fifth embodiment of an injection moulding device, obliquelyfrom above;

FIG. 6 the embodiment from FIG. 5 obliquely from below;

FIG. 7 the embodiment of FIG. 5, from the front;

FIG. 8 the embodiment of FIG. 5, from above;

FIG. 9 shows a sixth embodiment of an injection moulding device;

FIG. 10 shows an opened injection moulding device from above;

FIG. 111 shows the injection moulding device of FIG. 10 closed.

FIG. 1 shows a first embodiment of an injection moulding device 1according to the invention, with an injection moulding machine 2. Theinjection moulding device 1 contains a first, stationarily arrangedmould half 3 and a second mould half 5 displaccably arranged(y-direction) along guide means 4. The fist stationary mould half 3 isfastened on a stationary first mould clamping plate 42, and thedisplaceable, second mould half 5 on a second mould clamping plate 43displaceable along tie-bars 4, of the injection moulding machine 2.

In the shown embodiment, the tie-bars 4 of the injection mouldingmachine 2 serve as guide means 4. The tie-bars 4 in the front region areonly represented partly (sectioned), so that an improved view of theinjection moulding machine 1 is possible. A first and a second, middlepart 6, 7 may be recognised between the first and the second mould half3, 5. The first and the second, middle part 6, 7 in each case have anessentially parallelepiped upper part 12, 13 (mould carrier) with cavityhalves (not shown in detail, cf. FIG. 2), which in each case arearranged rotatably driven about a rotation axis 8, 9 which here isarranged vertically (z-direction). The first and the second, middle part6, 7 are mounted by way of guide means, here in the form of two guiderails 11 arranged parallel to the tie-bars 4 and arranged between theseon a machine bed 18 of the injection moulding machine 2. The middleparts 6, 7 in each case comprise a mounting 10 in the form of a base 14,15 which is movably arranged along the guide rails 11.

Depending on the embodiment, the mould carriers 12, 13 (upper parts) andthe bases 14 (lower parts) are releasably connected via standardisedinterfaces (not shown in more detail) for the transfer of media such aswater, air, electricity, hydraulics and electrical and mechanicalenergy. Commercially available, self-sealing quick couplings areparticularly suitable for the transfer of fluid and gaseous media. Thetransfer of electrical energy and digital information is usuallyeffected by way of plug-and-socket connections which are suitable forthis.

With the shown embodiment, the exchange of media and of energy iseffected between the upper part 12, 13 and the lower part 14, 15 of themiddle parts 6, 7, preferably coaxially through the corresponding rotaryshaft. All media and energy leads (not represented in more detail) arepreferably actively connected to the lower part 14.

With the shown embodiment, the upper parts 13 are only held at one side.The bases 14, 15 of the middle parts 6, 7 comprises preferably in eachcase a rotary unit 16, 17 which serve for rotating the upper part 12, 13about its respective, here vertical rotary axis 8, 9 (z-direction) withrespect to their base 14, 15. The rotary units 16, 17 are arrangedbetween the bases 14, 15 and the upper parts 12, 13 and comprise coaxialchannels and openings which serve for the exchange of media and energybetween the lower parts 14, 15 and the upper parts 13. The injectionmoulding device 1 and the centring means 26, 27 are designed such thatthey may be opened and closed in 90°- and/or 180°-steps.

The guide rails 11 are a constituent of the injection moulding machine2, depending on the embodiment, and are preferably fixedly connected tothe machine bed 18 of the machine. Alternatively, the guide rails 11 area constituent of an injection moulding device 1 and are removed out ofthe injection moulding machine 2 by way of this device, in the case forexample of an exchange of the mould. The guide rails 11 or the mounting10 of the upper parts 12, 13 are preferably designed such that they maybe adjusted in angle and alignment, so that a precise alignment withrespect to the mould halves 3, 5 and the guide means 4, 11 is possible.

The second, movably arranged mould half 5 is driven via a firsthydraulic cylinder 20 which simultaneously serves for producing theclosure force of the injection moulding machine 2, acting between thefirst and the second mould half 3, 5. Alternative embodiments such astoggle lever mechanisms known from the state of the art are possible. Adrive of the second mould half 5 which is realised via the tie-bars 4 ispossible depending on the embodiment. The two middle parts 6, 7 comprisea drive, shown schematically here as a spindle drive 21. The spindledrive 21 in the shown embodiment acts in the foot region of the middleparts 6, 7, in the vicinity of the guide rails 11, and serves for movingthe middle parts 6, 7 or opening and closing the parting planes 22, 23,24 in coordination for the movement of the second mould half 5. As arule, the spindle drive 21 is designed such that the middle part 6 ismoved essentially with ⅓ and the second, middle part 7 essentially with⅔ of the speed of the second mould half 5. By way of this, one succeedsin achieving equal distances in the opened condition, between the mouldhalves 3, 5 and the middle parts 6, 7. Other drive means, e.g. hydrauliccylinders or electric drives are possible, depending on the embodiment.Depending on the embodiment, transmission ratios other than 1/4, 2/4,1/4 may be preferred, so that the distances between the parts havedifferent measures on opening the mould.

The injection closure device 1 is shown in the opened condition in theshown representation. The cavities (not shown in detail) which arearranged in a first, a second and a third parting plane 22, 23, 24 areopened in this position. The mould halves 3, 5 and the middle parts 6, 7are travelled so far apart that the middle parts may be rotated togetheror independently of one another about their rotation axes 8, 9.

A first plastification unit 28 which here is arranged on a machine bed18 behind the first mould half 3 serves for the injection of the plasticmolten mass (not shown in more detail) into the cavities arranged in theregion of the first parting plane 22, when the injection moulding device1 is closed. A second plastification unit 29 which here is arrangedbehind the injection mould device 1 and essentially at a right angle tothis, serves for injecting plastic molten mass into cavities which arearranged in the region of the second parting plane 23. The secondplastification unit 29 is designed such that only with a closedinjection moulding device 1, is it actively connected to this, and doesnot prevent an opening of this. Alternatively or supplementarily, thepossibility exists of providing an injection device which is permanentlyactively connected to the second mould half and which e.g. is arrangedabove the first hydraulic cylinder 20.

Centring means, here in the form of centring lugs 26 and centring bores27 serve for capturing and centring the mould halves 4, 5 and the middleparts 6, 7 after the rotation of the middle parts 6, 7 about theirrotation axes 8, 9 by way of the rotation units 16, 17. The centringmeans prevent the cavities in the parting planes 22, 23, 24 from gettingdamaged, e.g. as a result of an incorrect position on closing theinjection moulding device 1. Depending on the held of application, thecentring lugs 26 and/or the centring bores 27 are designed in a fullmanner or conical in regions, so that an optimal centring is achieved.The centring lugs 26 and the centring bores 27 are arranged alternatingin a rotationally symmetrical mauler with respect to the rotational axes8, 9, so that the two mould halves 4, 5 and the two middle parts 6, 7 ofthe injection moulding device 1 may be closed at all. In contrast to aninjection moulding machine with no or only one middle part, thearrangement of the centring means must fulfil a special arrangement. Asmay be recognised, the centring means 26, 27 here are arranged in theedge region of the mould halves 4, 5 or the middle parts 6, 7. Otherarrangements are possible. The centring means 26, 27 if required may bedesigned such that when the injection moulding device is closed, theyserve for the removal of the injection moulding device 1 from theinjection moulding machine 2.

FIG. 2 shows a second embodiment of an injection moulding device 1 in aperspective view obliquely from above. The numbering corresponds to thatof FIG. 1, so that regions which are not described here are deduced fromFIG. 1. The shown injection moulding device 1, between a firststationary mould half 3 and a second mould half 5 which is movable inthe direction of tie-bars 4 (y-direction), comprises a third mould half19 which is movably arranged in the direction of the tie-bars 4, isarranged between the first middle part 6 and the second, middle part 7,and as a rule comprises cavity halves on two oppositely lying sides. Theinjection moulding device 1 comprises a first, a second, a third and afourth parting plane 22, 23, 24, 25 between the first mould half 3 andthe first middle part 6, the first middle part 6 and the third mouldhalf 19, the third mould half 19 and the second, middle part 7, and thesecond, middle part 7 and the second mould half 5 respectively. Themould halves 3, 5, 19 and the middle parts 6, 7 in the region of theparting planes 22, 23, 24, 24 respectively comprise cavities 38 intowhich plastic molten mass is injected by way of a first longitudinallyarranged, and a second and third laterally arranged plastification unit28, 29, 30 when the injection moulding device is closed. Theplastification units 28, 29, 30 are arranged in a stationary manner withthe shown embodiment. The second and the third, laterally arrangedplastification units 29, 30 are designed such that they are decoupled onopening the parting planes 22, 23, 24, 25. Another arrangement of theplastification units is possible, depending on the field of application.

The first and the second, middle part 6, 7 are in each case rotatablyarranged about a rotation axis 8, 9 which is vertical here. In contrastto the embodiment described in FIG. 1, the middle parts 6, 7 of theembodiment shown here are not only mounted at the bottom in the regionof the machine bed 18, but also at the top by way of a first and asecond upper crossmember 31, 32. The mounting 10 and the guiding of theupper parts 12, 13 of the middle parts 6, 7 in each case comprises abase 14, 15 supported on the machine bed 18, and in each case an uppercrossmember 31, 32. The device is designed such that it may be simplyremoved firm the injection moulding machine.

The third mould half 19 in the lower region is guided on the guide rails11, and in the upper region by way of a third, upper crossmember 33. Thecrossmembers 31, 32, 33, are displaceably designed along the tie-bars 4.The drive (not shown in more detail) of the middle parts 6, 7 and thethird mould half 19 in the tie-bar direction (y-direction), as a rule isdesigned such that on opening and closure of the injection mouldingmachine 1, the first middle part 6 is moved with essentially ¼, thethird mould half 19 essentially with 2/4 and the second, middle par 7essentially with ¾ the speed of the second mould half 5, so that theinjection moulding device is uniformly opened in the region of theparting planes 22, 23, 24, 25. Other transmission ratios are possible.

The linear drive in the y-direction is effected preferably by way of anactive or passive single-sided or two-sided spindle drive, by way of arack drive or by way of hydraulic cylinders. When required, a rack maybe integrated into the rail system. An active drive system is to beunderstood as a drive which has its own energy supply and permits anautomatic movement of the moving parts. A passive drive system is to beunderstood as a drive which is directly or indirectly actively connectedto the hydraulic drive 20 of the injection moulding machine 2. Apreferred embodiment of a passive drive comprises coordinating spindles.Preferably one electric or one hydraulic motor which is directly, or viaa gear, is indirectly actively connected to the rotation shafts of themiddle parts 6, 7 is applied per middle part 6, 7 as a drive 40 for therotation of the here parallelepiped upper parts 12, 13 of the middleparts 6, 7 about their rotation axes 8, 9.

The two-sided mounting amongst others offers the advantage of a moreprecise guiding, and of a drive being possible at the bottom as well asat the top, so that the mass forces are reduced with a largeracceleration. For the removal of the injection moulding device 1 fromthe injection moulding machine 2, the crossmembers 31, 32, 33 of theshown embodiment are preferably designed such that the active connectionwith the tie-bars 4 of the injection moulding machine 2 may be released.The release of the active connection is effected in the region of therotation units 16, 17 of the middle parts 6, 7 or between the bases 14,15 (lower parts) and the guide rails 11, depending on the embodiment. Itis possible to remove the injection moulding device 1 out of theinjection moulding machine from the top and when required to insert itinto this again, on account of slim design of the mounting and thesimple separation of the active connections. Represented in a simplifiedmanner, the mounting of the middle part in the upper region comprises acrossmember which may be actively connected to the tie-bars 4 of aninjection moulding machine 2, and in the lower region comprises a railsystem which is mounted on the machine bed 18 of the injection mouldingmachine 2. With one embodiment, the upper part serves as a mould, mouldhalf or mould carrier. So that the upper part of the middle part isrotatable about a rotation axis, a lower and an upper rotation unit areprovided in the region of the lower part and in the region of the uppercrossmember, and these units if required, comprise channels in theinside which serve for the coaxial supply of media for the upper part.

The embodiment shown here is particularly suitable for the manufactureof multi-part plastic parts which consist of several plastic components.One manufacturing method may be seen as follows. With a closed injectionmoulding device 1, plastic parts are formed essentially simultaneouslyin the region of the four parting planes 22, 23, 24, 25 by way ofinjecting plastic molten mass into cavities 38. The cavities 38 aresubsequently opened by way of moving apart the first, the second and thethird mould half 3, 5, 19 and the middle parts 6, 7. The parts formed inthe cavities 38 remain sticking to the upper parts 12, 13 of the middleparts 6, 7 and are led to the next processing step by way of these.

A processing procedure, represented in a simplified manner, isimplemented generally as follows. With a closed injection mouldingdevice, a first plastic component is injected into one or more cavities38 in the region of the third parting plane 24, so that parts are formedof the fist plastic component. Simultaneously, parts of the firstplastic component which were previously transported with the first upperpart 12 of the first middle part 6 in two 90°-steps in the anticlockwisedirection about the rotation axis into the region of the first partingplane 22 are actively connected to a second plastic component in theregion of the first parting plane 22. Essentially simultaneously, againparts are formed from the first plastic component in the region of thethird parting plane 24. The parts from the first parting plane 22,consisting of the first and the second plastic component, by way ofrotating the first upper part 12 by 90° about the first rotation axis 8,are subsequently brought into the free front region (opposite the secondand the third plastification unit 29, 39) of the injection mouldingdevice, where they are led to a further processing step. A third plasticcomponent is injected into cavities 38 in the region of the secondparting plane 23, so that parts are formed. Essentially simultaneously,parts of this third plastic component, in the region of the fourthparting plane 25, are actively connected a fourth plastic component, inthat this is injected into the cavities which are partly formed by theparts of the third plastic component. The parts of the third plasticcomponent, with an opened injection moulding device, are previouslybrought into the region of the fourth parting plane 25 by way of thesecond upper part 13. Another sequence of processing steps is alsopossible, as the case may be.

The plastic parts manufactured in the four parting planes 22, 23, 24, 25are removed from the injection moulding device 1 and/or are assembled byway of a robot (not shown in more detail), in the front region of theinjection moulding device 1, opposite the second and the thirdplastification units 28, 29. Further processing steps, for examplemarking the plastic parts or a cooling phase may be provided in the rearregion of the injection moulding device 1. If required, the injectionmoulding machine may comprise more that two middle parts 6, 7 and/orthird mould halves 19.

In a further embodiment of the invention, the third mould half 19 as thetwo middle parts 6, 7 are rotatably arranged about a third rotation axis(not shown in more detail). The third mould half 19 has a suitablemounting for this purpose. This permits the manufacture of verycomplicated plastic parts in a single injection moulding device. Ifrequired, there is the possibility of combining the middle parts with 2,4 or 6 sides in the same injection moulding device. Further processingsteps may for example be realised by robots.

FIG. 3 shows a further embodiment of an injection moulding device 1 in aperspective representation obliquely from above. A stationary firstmould half 3 is fastened on a stationary mould clamping plate 42. Asecond mould half 5 is attached to a second mould clamping plate 43which is displaceably arranged along tie-bars 4.1, 4.2 of an injectionmoulding machine (not shown in more detail). A first and second, middlepart 6,7 with a mould carrier 12, 13 each rotatable about a rotationaxis 8, 9 with respect to a base 14, 15 are arranged between the firstand the second mould half 3, 5. The bases with the shown embodiment aredesigned as crossmembers 14, 15 which in the shown embodiment areactively connected to the lower tie-bars 4.1 of the injection mouldingmachine. The crossmembers 14, 15 are driven in a displaceable manneralong the tie-bars 4. The active connection between the crossmembers 14,15 and the tie-bars 4.1 may be simply released so that the injectionmoulding device 1 may be installed and removed in a simple manner. Witha further embodiment, the crossmembers 14, 15 are in active connectionwith the upper two tie-bars 4.2, and the middle parts 6, 7 are arrangedin a suspended manner. This embodiment has the advantage that anexchange of the injection moulding device is possible in a particularlysimple manner.

The mould carriers 12, 13 are actively connected to the crossmembers 14,15 rotatably about the rotation axes 8, 9 by way of rotation units 16,17. The rotation units 16, 17 are preferably designed such that themould carriers 12, 13 are rotatable about the rotation axes 8, 9 in anendless manner. The rotation units 16, 17 comprise channels in theinside, which serve for the exchange of operating material and thesupply of energy to the mould carriers 12, 13. The rotation units 16, 17are provided with a drive for the rotational movement of the mouldcarriers 12, 13 about the rotation axes 8, 9. Preferably electric andhydraulic motors are used for the drive. When required, the crossmembers14, 15 are supported below the machine bed (cf. FIG. 1), in order to beable to better distribute the weight of the middle parts. Partinglocations may be provided between the crossmembers 14, 15 and the mouldcarriers 12, 13, and permit a parting of the mould carriers 12, 13 fromthe lower parts 14, 15.

FIG. 4 shows a further embodiment of an injection moulding device in aperspective representation obliquely from above. A first and a secondmould half 3, 5 as well as a first and a second, middle part 6, 7rotatable about an axis 8, 9 which is vertical here, are arrangedbetween a first stationary mould clamping plate 42, and a second mouldclamping plate 43 which is movable along tie-bars 4. The middle parts 6,7 here comprise parallelepiped mould carriers 12, 13 which are supportedon two sides by way of a lower and an upper crossmember 48, 49 oppositethe tie-bars 4 of an injection moulding device which is not representedin more detail. The crossmembers 48, 49 comprise holding means 50 whichare releasably actively connected to the mould carriers 12, 13 viainterfaces. The holding means 50 may be displaced relative to oneanother, such that the mould carriers 12, 13 may be removed from theinjection moulding machine. The holding means 50 comprise standardisedinterfaces which serve for the transfer of media to the mould carriers12, 13. Centring means, here in the shape of centring lugs 26 andcentring bores 27 are arranged in a rotationally symmetrical manner,such that they engage into one another in the closure positions of themould carriers 12, 13 on closure of the injection moulding device 1. Thecentring means 26, 27 are designed such that they are suitable for thecorrection of a certain incorrect position of the mould carriers 12, 13as a result of a rotation about the rotation axes 8, 9 against towardsone another, or of the mould halves 3, 5. In contrast to rotary systemsknown from the state of the art, the exact pre-centring of the rotatableparts with the invention disclosed here is of particular importance,since incorrect positions are considerably more likely due to the manymoving parts. For this reason, the centring means as a rule are designedsuch that they permit a centring of the mould before this is completelyclosed or the sensitive cavities engage into one another. With apreferred embodiment, the centring means have a length which correspondsto roughly double the diameter of the centring means.

FIG. 5 and FIG. 6 show a further embodiment of an injection mouldingmachine 1 in a perspective representation obliquely from above/thefront, and obliquely from below/the rear. FIGS. 7 and 8 show the sameinjection moulding device 1 front the front (FIG. 7) and from above(FIG. 8). The numbering in these three Figures corresponds to oneanother. Not all reference numerals are present simultaneously in allfigures. The injection moulding device 1 is shown in the openedposition, i.e. with opened parting planes 22, 23, 24.

The injection moulding device 1 is arranged between a first stationarymould clamping plate 42 and a second mould clamping plate 43 which ismovable along tie-bars 4 (y-direction), of an injection moulding machine(not shown in more detail). The injection moulding device 1 comprises afirst mould half 3 with cavity halves 38 which is actively connected tothe first mould clamping plate 42. A second mould half 5 with cavityhalves 38 is actively connected to the movable mould clamping plate 43.A first and a second, middle part 6, 7 are arranged between the firstand the second mould halves 3, 5, and are in each case rotatable about avertical axis 8, 9 (z-direction) which is essentially perpendicular tothe tie-bars 4.

Each middle part 6, 7 comprises a lower and an upper crossmember 48, 49(x-direction) which are mounted on the tie-bars 4 of the injectionmoulding machine in a longitudinally displaceable manner via bearings51. In the shown embodiment, the bearings 51 are designed such that theymay be separated, so that they may be simply released from the tie-barsof the injection moulding machine for the purpose of the removal of theinjection moulding device 1 from the injection moulding machine by wayof removing lower bearing shells. The crossmembers 48, 49 of each middlepart 6, 7 in each case comprise one holding means 50 which serves forthe mounting of a mould carrier 12, 13 with cavities 38, which isarranged therebetween and here is parallelepiped. The holding means ofeach middle part 6, 7, said holding means being allocated to oneanother, are mounted aligned to one another and rotatably with respectto the crossmembers 48, 49 about rotation axes 8, 9. The holding means50 are actively connected to the crossmembers 48, 49 which are allocatedto them by way of bearing units 54 which are rotatable about rotationaxes 8, 9. The bearing units 54 preferably comprise pre-stressedbearings which ensure a precise guiding. The holding means 50 arepreferably connected to the mould carriers via quick couplings, so thatthe mould carriers may be installed and removed in a simple manner. Withcertain embodiments, the holding means 50 are arranged displaceable toone another in the horizontal and/or vertical direction, so that themould carriers may be installed and removed without removal of at leastof one of the crossmembers. The holding means 50 when required arearranged such that they may be individually adjusted in the verticaland/or horizontal direction in a certain range for a finesetting/adjustment.

With the shown embodiment, the bearing units 54 simultaneous serve forthe exchange of media with the mould carriers 12, 13. For this purpose,the bearing units 54 comprise connections 55 for media conduits such aswater, hydraulic oil, etc. Further interfaces for the exchange ofinformation and electrical energy are likewise preset if required. Theexchange of media with the mould carriers 54 as a rule is effectedcoaxially through inner hollow shafts (may not be recognised) of thebearing units 54 and via the holding means 50. The coaxial transfer ofmedia is preferably effected from the lower side and/or the upper side.

With the shown embodiment, the rotational drive of the mould carriers12, 13 about the rotation axes 8, 9 is effected from the upper side viathe bearing units 54. Each middle part 12, 13 comprises a servomotor 56which is actively connected to the mould carrier 12, 13 via a toothedbelt 57. With certain embodiments, the servomotor is integrated into thebearing units 54. The mould carriers 12, 13 may rotate about therotation axes 8, 9 in a precise manner by way of the servomotor 56. Dueto the coaxial transfer of media, there exists the possibility ofinfinitely rotating the mould carriers about their rotation axes 8, 9.

With the shown embodiment, the middle parts 6, 7 of the injectionmoulding device 1 are supported on the machine bed of the injectionmoulding machine (not shown in detail) between the tie-bars 4 (cf. FIG.6) by way of linear bearings 60. The linear bearings 60 serve forcompensating the weight of the middle parts 6, 7 and for the partialload alleviation of the tie-bars 4. They also serve as aids forinstalment and removal. The linear bearings 60 cooperate with rails 61which are arranged on the machine bed of the injection moulding machine.If required, the bearings 51 as well as linear bearings 60 may beadjusted in angle, position and alignment with respect to the mainmovement direction (y-direction), or the direction of the tie-bars 4 ofthe injection moulding device.

With a closed injection moulding device 1, parts are manufactured by wayof injecting plastic into cavities 38 in the region of the first andsecond parting plane 22, 23. The injection into the cavities 38 in theregion of the first parting plane 22 as a rule is effected through aninjection opening 44 in the stationary mould clamping plate 42. Theinjection of plastic into cavities of the second parting plane 23 ispreferably effected by an injection apparatus which is arrangedlaterally next to, or above the injection moulding device 1 and which isactively connected to the injection moulding device either onlytemporarily during the injection procedure, or is constantly connectedto this and moves with it. The injecting is effected either directly orvia the second, moving mould clamping plate 43. Parts (not shown in moredetail) manufactured previously in the first and second parting plane22, 23 are actively connected to one another in the region of the thirdparting plane 24. The parts for this purpose remain sticking to thecavity halves 38 on the mould carrier side 12, 13 on opening the firstand second parting plane 22, 23, and are brought from the first or thesecond parting plane 22, 23 into the region of the third parting plane24 by way of rotating the mould carriers 12, 13 respectively. For this,the mould carriers 12, 13 as a rule are rotated by 90° or by 180° aboutthe rotation axes 8, 9. In the case of 90°-steps, the parts aretransported into the region of the third parting plane 24 in two steps,so that they are arranged laterally on the injection moulding deviceduring the intermediate step. In this position, the parts may eithercool down or be subjected to a further processing step by way of anexternal device or one which is integrated into the injection mouldingdevice.

The injection moulding device 1 comprises coordination means 65 whichcoordinate the movement of the moving parts on opening and closure ofthe injection moulding device 1. The shown embodiment comprises fourcoordination means 65, of which in each case two are actively connectedto the stationary mould clamping plate 42, the upper two crossmembersand the moving mould clamping plate 43, and in each case two to thestationary mould clamping plate 42, the lower two crossmembers 48 andthe moving mould clamping plate 42. The coordination means 65 aredesigned as modules which are attached at essentially the height of thetie-bars 4 and prevent a lateral tilting of the tie-bars 48, 49 onopening and closing the injection moulding device 1. The coordinationmeans 65 are fastened on the mould clamping plates 42, 43 and thecrossmembers 48, 49 via releasable connections 66. The coordinationbetween the moving parts of the injection moulding device 1 is lifted byway of removing the coordination means 65, so that the crossmembers 48,49 are displaceable along the tie-bars 4 independently of one anothere.g. on removal or insertion of the mould halves 3, 5 or of the mouldcarriers 12, 13.

Each of the four coordination means 65 of the shown embodiment comprisesa first, a second and a third spindle 67, 68, 69 which are activelyconnected to one another. Each of the spindles is divided into two andin the first half comprises a first thread with a positive pitch, and inthe second half a second thread 71 with a negative pitch which setopposite to the first. In the middle, the spindles are activelyconnected via torsion-free axial bearings 72 to a spindle block 73(first spindle) or to the crossmembers 48, 49 of the first and second,middle part 6, 7 respectively (second and third spindle respectively).The threads of the first spindle 67 are actively connected tocorresponding, stationary spindle nuts 74, which are fastened onhorizontally arranged carriers 75. The carriers 75 in turn are fixedlyconnected to the first and the second mould clamping plate 42respectively. If then, the second mould clamping plate 43 is movedrelative to the fist mould clamping plate 42, the fist spindle 67 beginsto rotate on account of the counter running threads on the two sides.Thereby, the rotational speed is dependent on the pitch of the outerthread 70, 71 or the inner thread of the spindle nuts 74. With the shownembodiment, the two threads 70, 71 have the same counter running threadpitch, so that a uniform screwing of the first spindle 67 into thespindle nut 74 results. Due to this, the spindle block is always locatedin the middle (with respect to the travelled path) between the fist andsecond mould half 3, 5 on respectively opening and closing the injectionmoulding machine 1. With the shown embodiment, the middle block moveswith half the speed with respect to the relative speed between thestationary first mould clamping plate 42 and the moving second mouldclamping plate 43.

The second spindle 68 which is arranged between the first mould clampingplate 42 and the spindle block 73 or the third spindle 69 arrangedbetween the spindle block 73 and the second mould clamping plate 43 haveessentially the same construction as the first spindle 67. The second orthe third spindle 68, 69 are actively connected to the crossmembers 48,49 respectively in the region of their middle by way of an axialbearings 72. The relative speed of the crossmembers of the first middlepart 6 is therefore determined by the relative speed between thestationary, first mould clamping plate 42 and the spindle block 73, andthe speed of the crossmembers 48, 49 of the second, middle part 7 by therelative speed between the spindle block 73 and the second mouldclamping plate 43. By way of the described coordination mechanism 65,one succeeds in moving the first middle part 6 on opening and closingthe injection moulding device 1 with a quarter, and the second, middlepart 7 with three quarters of the speed of the second mould clampingplate 43, so that the distance y2 between the two middle parts 6, 7 orthe two mould carriers 12, 13 in the region of the third parting plane24 is essentially twice as large as the distances y3 and y4 between thefirst mould half 3 and the first mould carrier 12, and the second mouldcarrier 13 and the second mould half 5 respectively, in the region ofthe first and second parting plane 22, 23 respectively. By way of thismovement of the middle parts 6, 7 with respect to the mould clampingplates 42, 43, one succeeds in being able to move the mould carriers 12,13 much earlier about the rotation axes 8, 9 without them colliding withone another, than if the injection moulding device 1 were uniformlyopened so that the distances y2, y3, y4 were equally large.

By way of the selection of the pitches of the spindles 67, 68, 69, thereexists the possibility of being able to set the distance y1 between therotation axes 8, 9 or the distances y2, y3, y4 in a largely free manner.By way of the selection of different pitches of the two allocatedthreads of a spindle, one may influence the ratio such that, e.g. thepart which is co-guided in the region of the spindle middle, is co-movedwith a defined speed with respect to the second mould clamping plate 43.The described coordination means 65 may be used in a suitable manneralso with injection moulding devices 1 with which the middle parts 6, 7have a different mounting/support with respect to the tie-bars. Themiddle block 73 many be used for guiding a third mould half, as is shownin FIG. 2.

On removal of the described injection moulding device 1 from astandardised injection moulding machine 1, the four coordination means65 are removed, so that the middle parts are freely movable relative toone another. With an opened injection moulding device, the bearingshells 52 of the bearings 51 of the upper crossmembers 49 are released.After the release of the lower holding means 50 and all media supplyconduits and cable connections, the mould carriers 12, 13 may be removedtogether with the upper crossmembers 49. Depending on the embodiment,firstly only the upper holding means 50 are released, and firstly onlythe upper crossmembers 49 and only then the mould carriers 12, 13. Thebearings 50 of the lower crossmembers may then be subsequently openedand the lower crossmembers 48 removed. Preferably the travelled paths ofthe moved parts are matched to one another depending on the partingplane by way of a coordination mechanism, such that the middle parts maybe rotated efficiently and when required, simultaneously (cf. FIG. 8,here schematically indicated by circles k1 and k2 on which the outerpoints of the mould carriers 12, 13 rotate).

The parts from the first and the second parting plane 22, 23 areactively connected to one another in the region of the third partingplane 24. In a preferred embodiment, this is effected by way ofperipheral injection with a material component, which for example isinjected laterally or from above into further cavities (not shown inmore detail). In a preferred embodiment, these further cavities resulteither on account of a cooperation of the cavities 38 of the first andof the second mould carrier 12, 13 or alternatively or supplementarilyby way of displacing a part of the injection mould e.g. of a slide (notshown in detail), in a mould carrier 12, 13. The injecting into thefurther cavities is preferably effected by way of a separate injectionassembly of the described form.

Alternatively or supplementarily, the parts of the first and of thesecond parting plane 22, 23 are mechanically joined together or activelyconnected in a direct or indirect manner in the region of the thirdparting plane 24. In a first embodiment, this is effected by way of theclosure movement of the injection moulding device 1, which however undercertain circumstances entails the disadvantage that the injectionmoulding device may not be closed with the maximal possible speed, orthere exists the danger that the parts and/or the injection mould aredamaged. A further problem lies in the fact that the relative movementin this variant is very difficult to control and adjust due to the highmass of the moved parts. In a further embodiment of the invention, aseparate active connection device is present, which is suitable forjoining the parts together. In a preferred embodiment, at least one ofthe mould carriers 12, 13 is provided with a separate active connectiondevice which is capable of functioning decoupled from the closuremovement of the injection moulding device 1. The active connectiondevice as a rule is at least partly arranged in the inside, and is inactive connection with parts which are arranged in the cavity halves 38of the first and/or the second mould carrier 12, 13. When required, theactive connection device has a construction which permits an adjustmentof the force and/or path per cavity or group of cavities. The activeconnection device is designed such that the parts of the correspondingcavities 38 which are to be connected to one another are capable ofbeing joined together with a closed injection moulding device 1. Theactive connection device is preferably hydraulically, mechanically,and/or electrically driven and may in regions be designed as part of acavity. In one embodiment, the active connection device is designed asan active connection slide which is designed as one or more parts. Whenrequired, each cavity 38 may bc designed with a separate activeconnection device. The active connection device may be designed suchthat it is only applied with a closed injection moulding device.Alternatively or supplementarily, the active connection device may bedesigned such that a superposition or utilisation of the closuremovement of the injection moulding device 1 is used for the joining ofthe parts to be connected.

Depending on the field of application, the parts to be connected arejoined together by way of the active connection device in one step or inseveral individual steps. For example, there exists the possibility ofbringing at least the parts of one side into a certain position orreleasing them, before the actual active connection procedure iseffected. If required, the parts may be subjected to a furtherprocessing step, e.g. in that they are at least partly peripherallyinjected or welded, after the active connection device has stepped intoaction.

One of the advantages of a separate active connection device lies in thefact that the parts to be connected to one another are processed in verymuch more precise and gentle manner. In particular, a joining togetheronly by way of the closure movement of the injection moulding device ismostly inadequate, in particular with injection moulding devices whichcomprise a multitude of cavities in a parting plane.

FIG. 9 shows a further embodiment of an injection moulding device 1 in aperspective representation obliquely from above. A stationary firstmould half 3 is fastened on a stationary mould clamping plate 42. Asecond mould half 5 is attached on a second mould clamping plate 43which is displaceably arranged along tie-bars 4 of an injection mouldingmachine (not shown in more detail). A first and a second, middle part 6,7 with in each case a mould carrier 12, 13 rotatable about a first orsecond rotation axis 8, 9 are arranged between the first and the secondmould half 3, 5.

The first and the second, middle part 6, 7 here are each mounted withrespect to the mould halves 2, 3 or the mould clamping plates 42, 43 byway of a lower and an upper cantilever arm 36, 37. The cantilever arms36, 37 serve as a base and as a linear guide. The cantilever arms 36 ofthe first middle part 6 are arranged in a stationary manner with thefirst mould half 2. In contrasts to this, the cantilever arms 37 whichserve for mounting the second, middle part 3, are actively connected tothe second mould half 5 or the second mould clamping plate 43 and movedwith these.

The mould carriers 12, 13 are actively connected to the cantilever arms36, 37 in a rotatable manner about the rotation axes 8, 9 by way ofrotation units 16, 17. The rotation units 16, 17 are preferably designedsuch that the mould carriers 12, 13 are endlessly rotatable aboutrotation axes 8, 9, and in the inside comprise channels which serve forthe exchange of operating material and the supply of energy to the mouldcarriers 12, 13. The rotation units 16, 17 are provided with a drive forthe rotation movement of the mould carriers 12, 13 about the rotationaxes 8, 9. Preferably electric or hydraulic motors are used as a drive.The cantilever arms are preferably designed such that the middle partsmay be moved independently of one another with respect to the first orthe second mould half.

With the shown embodiment, the middle parts 2, 3 are displaceablyarranged in the longitudinal direction with respect to the cantileverarms 36, 37 (schematically represented by arrows y5, y7). Thereby, theyare displaced and positioned along the cantilever arms 36, 37 by way oflinear drives 41. The movement during the production is matched to themovement (arrow y7) of the second mould ha such that no cycle time islost and an as time-saving as possible rotation of the middle parts ispossible. The parting planes are preferably opened in a non-uniformmanner for the purpose of an efficient rotation of the mould carrier 12,13 about the rotation axes 8, 9. When required, the weight of the middleparts may be compensated by way of additional supporting, e.g. on themachine bed of the injection moulding machine (not shown in moredetail), or via the tie-bars 4. The centring and alignment of theindividual parts is effected in the described manner. Spindles, toothedbelts, racks or hydraulic cylinders are conceivable as linear drives.Passive solutions may comprise a mechanical coupling with the movablemould half 3. The cantilever arms as designed as lin=ar guides or areactively connected to such.

The mould carriers 12, 13 in the region of their side surfaces comprisecorresponding cavities (not shown in more detail) into which plastic isinjected given a closed injection moulding device 1. The mould carriers12, 13 are provided with active connection means which given a closedinjection moulding device serve for the assembly of injection mouldedparts in the middle closure plane. An active connection means isallocated to one or more cavities and may be individually activated whenrequired. The shown embodiment amongst others is suitable for smallerdevices.

FIGS. 10 and 11 schematically show an injection moulding device 1 in theopened (FIG. 10) and in the closed position (FIG. 11). Shown are thestationary and moving mould clamping plate 42, 43 of an injectionmoulding machine (may not be recognised in more detail) on which astationary first and a moving second mould half 2, 3 are attached. Afirst and a second mould carrier may be recognised between the first andthe second mould half 2, 3, and are rotatably arranged about rotationaxes 8, 9, which here are perpendicular to the plane of the drawing.

In FIG. 10 it is shown in which position the mould halves 2, 3 arepreferably rotated about the rotation axes 8, 9. The distances y1 y2, y3and y4 are given by the rotational radii R which indicates the outermostpoint of the mould carrier 12, 13. The diagonal position in which themould carriers 12, 13 assume the maximal extension is indicated bysquares 12′, 13′. With the shown embodiment, the rotation is effectedmost efficiently if the distances y3 and y4 are selected roughly half aslarge as the distance y2 and the distances y3 and y4 such that therotation radii do not contact the first and the second mould half 2, 3respectively.

Active connection means 46 are represented in the FIGS. 10 and 11, whichgiven a closed injection moulding device 1, serve for the assembly ofparts in the region of the middle (second) parting plane 23. Furtherplastic parts are manufactured essentially simultaneously in the firstand the second parting plane 22, 24.

In the shown embodiment, both mould carriers 12, 13 comprise activeconnection means 46 which serve for the simultaneous joining of parts oftwo cavities allocated to one another. Depending on the field ofapplication, there exits the possibility of providing only one mouldcarrier 12, 13 or both in an alternating manner, with active connectionmeans 46, so that the joining of parts is effected in only one directionin the middle parting plane 23. When required one may also provideseveral active connection means which execute a multi-stage processingin a sequential or superimposed manner. If required, processing stepsand/or manipulations are possible with an opened device. The activeconnection means 46 of the middle parting plane are shown travelledtogether (cf. arrow y8) in FIG. 11, which is to represent an activeconnection process in a simple manner. One of the advantages of theshown device is the fact that the active connection of parts may bedecoupled by the main machine movement of the injection mouldingmachine.

With regard to the active connection means it is preferably the case ofindividual or several, individually or commonly actuatable slides, rakesor displacement means or a combination of these which are appliedsimultaneously or sequentially. The active connection means are moved orrotated parallel or perpendicularly to the main movement direction ofthe injection moulding machine according to function. Other movementforms are possible. The active connection means are preferably drivenvia hydraulics or electric motors, or by way of a mechanical coupling toother parts of the device. Complex movements may be realised e.g. by wayof involutes. If required, the movements and the forces may be monitoredby way of sensors per cavity or a group of cavities. When required, theactive connection means serve for ejecting the finished parts with anopened injection moulding machine.

Further embodiments may be deduced by the man skilled in the art by wayof combination of the features of the described devices.

1. An injection molding device with a stationary first mold half, with asecond mold half displaceably arranged in the direction (y) of tie-barsof an injection molding machine, with a first and a second, middle partarranged between the mold halves and displaceable in the direction ofthe tie-bars and each with a mold carrier rotatable about a rotationaxis with respect to a mounting, wherein at least one active connectionmeans is present in the region of at least one side surface of a moldcarrier and services for actively connecting parts in the region of themiddle parting plane.
 2. An injection molding device according to claim1, wherein the at least one active connection means is designed suchthat it actively connects parts of one or more pairs of cavitiesallocated to one another, to one another.
 3. An injection molding deviceaccording to claim 1, wherein at least one active connection means has aseparate drive, by way of which it may be moved independently.
 4. Aninjection molding device according to claim 1, wherein at least oneactive connection means comprises a rake, a slide or a dislocatingmeans.
 5. An injection molding device according to claim 1, wherein theactive connection device at least partly, is arranged in the inside of amold carrier.
 6. An injection molding device according to claim 1,wherein centering means which serve for centering the middle parts withrespect to the mold halves on opening and closing the injection moldingdevice, are axially symmetrically arranged in a manner such that theinjection molding device may be closed in 90°- and/or 180°-steps.
 7. Aninjection molding device according to claim 1, wherein a base or acantilever arm comprise a locking pin, and a mold carrier comprises alocking opening into which the locking pin engages in predefinedpositions.
 8. An injection molding device according to claim 1, whereinthe mold carrier is releasably connected to a base via a rotation unit.9. An injection molding device according to claim 1, wherein the middleparts are mounted with respect to a machine bed of the injection moldingmachine, or a cantilever arm, by way of a linear guide.
 10. An injectionmolding device according to claim 1, the middle parts are supported onthe lower and/or on the two upper tie-bars of the injection moldingmachine by way of a lower and/or an upper crossmember.
 11. An injectionmolding device according to claim 1, wherein the middle parts areadjustable in angle and alignment with respect to the first and thesecond mold half
 3. 12. An injection molding device according to claim1, wherein the relative movement of the mold halves and the mold carrieris coordinated by at least one coordination mechanism.
 13. An injectionmolding machine according to claim 12, wherein the coordinationmechanism is designed such that the parting planes are opened in theratio 1/4, 2/4, 1/4, (y3, y2, y4).
 14. An injection molding machineaccording to claim 12, wherein the coordination mechanism comprisesthree spindles which are actively connected to one another and which ineach case have a first region with a positive pitch and a second regionwith a second, negative pitch.
 15. An injection molding machineaccording to claim 12, wherein the spindles in the region of theirmiddle are actively connected to a spindle block or to a crossmember, byway of an axial bearing.
 16. An injection molding device according toclaim 14, wherein the spindles are actively connected in the region oftheir ends to a mold clamping plate or to a spindle block, by way of aspindle nut.
 17. A method for manufacturing a multi-part product in aninjection molding device which comprises the following method steps: a)essentially simultaneous manufacture of at least one first and secondpart n a first and a third outer parting plane of a closed injectionmolding device by way of injecting liquid plastic into cavities, whilstessentially simultaneously, a first and a second part are activelyconnected by way of an active connection means in the region of asecond, middle parting plane; b) opening the injection molding devicealong the parting planes and rotating a first and a second mold carrierin each case about a rotation axis about an angle, wherein the first andthe second parts manufactured in the first and the third parting planeare co-moved by way of the first and the second mold carrier sticking tothese; c) closing the injection molding device and repeating the steps ato c.
 18. A method according to patent claim 17, wherein the second,middle parting plane is opened roughly double as far as the first andthe third parting plane.
 19. A method according to one of the patentclaim 17, wherein active connection of the two first parts in thesecond, middle parting plane is effected independently of the movementof the mold clamping plates of the injection molding machine.
 20. Amethod according to patent claim 17, wherein the active connection ofthe two first parts in the second, middle parting plane is effectedindependently in groups of cavities allocated to one another.
 21. Amethod according to patent claim 17, wherein the parts are ejected byway of the active connection means.